DS90UB925 I2C Remote Access

HBKim

Prodigy 60 points

Hi,

We have following setup

Host ------ 926 EVM ------------ 925 EVM ------- Camera Sensor

We tried to access registers in 925 and Cam Sensor from host, but it doesn't work.

We set up 926[0x3] = 0xF8 and 926[0x7] = 0x18

reading from 926 works fine but access to 925 doesnt work at all.

We tried two 925 EVMs but it didn't work.

Regards,

Han-Bin

over 9 years ago

0 Mark Sauerwald88474 over 9 years ago

TI__Genius 13475 points

The 926 register 0x07 should be automatically loaded with the I2C address of the serializer - if you do not write it with 0x18, what value do you read from that register?

0 HBKim over 9 years ago in reply to Mark Sauerwald88474

Prodigy 60 points

It's 18. But I re-write again to 0x18.

0 HBKim over 9 years ago in reply to HBKim

Prodigy 60 points

Updates. We fixed I2C master logic to support clock stretching.
www.ti.com/.../getliterature.tsp
Also 926[0x5]'s value was 0x1e and write this to 0x9e: I2C Pass-Through All Transaction
Now I can access register 925 (0x18).

0 HBKim over 9 years ago in reply to HBKim

Prodigy 60 points

I restarted whole procedure to access Cam sensor.
926[0x8] = 6c ; SlaveID[0]
926[0x10] = 6c ; SlaveAlias[0]
and
926[0x3] = f8; Config. Was F0. Bit3 I2C Pass through
926[0x5] = 9e; I2C Config. Was 1e. bit7 i2C Pass Through All

Now I can read all 925 registers.
I cannot access Cam Sensor (0x6c)

I tried to write 925
925[0x3] = DA; Was D2. Bit2 I2C Pass-Through Enable
also read back 925[0x3]. Data is D2. This may mean I cannot write to 925?

Any suggestion to access Cam sensor?

0 HBKim over 9 years ago in reply to HBKim

Prodigy 60 points

Actually previous step is working. I was confused last time.

Regards, HBK

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DS90UB925 I2C Remote Access